Akiba's quite crowded these days so perhaps go early if you're hunting for specific merch. If you used to buy certain manga, check online if the store(s) are still open as I understand from my partner that some closed and the larger branch might be in Ikebukero.

Apple JP store doesn't provide tax free anymore. If you want a macbook with US style QWERTY keyboard, though, you will want the official Apple store. If you have a Costco membership or can shop around a bit, assuming you're from the US, keep an eye on slickdeals.net for deals. I know some people really wanted to buy Apple gear in Japan on prior threads due to the yen to dollar & tax free advantage but that was also when it was closer to ~155 jpy/1 usd.
Absolutely double check local prices for identical spec'd machines as US is often the least expensive for Apple gear. Also, with various tariff and de minimis for inbound packages, it might make sense to get it in the US especially if you visit sales tax free states or might have an edu/work/Apple employee friends and family discount. I don't think anything's been announced around changing duty free limits but some Apple gear will hit the $800 max for duty free. You wouldn't need to worry about possible after-purchase import duty/taxes on a US retail model.